﻿<p>The <em>IfcMappedItem</em> is the inserted instance of a source definition (to be compared with a block / shared
cell / macro definition). The instance is inserted by applying a Cartesian transformation operator as the
<em>MappingTarget</em>.</p>
<blockquote class="note">NOTE&nbsp; A mapped item is a subtype of representation item. It enables a representation to
be used as a representation item in one or more other representations. The mapped item allows for the definition of a
representation using other representations.</blockquote>
<blockquote class="example">EXAMPLE&nbsp; An <em>IfcMappedItem</em> can reuse other mapped items (ako nested blocks),
doing so the <em>IfcRepresentationMap</em> is based on an <em>IfcShapeRepresentation</em> including one or more
<em>IfcMappedItem</em>'s.</blockquote>
<blockquote class="extDef">NOTE&nbsp; Definition according to ISO/CD 10303-43:1992<br>
A mapped item is a type of representation item that specifies the mapping of a representation as an element of the
items of a second representation.</blockquote>
<blockquote class="note">NOTE&nbsp; Entity adapted from <strong>mapped_item</strong> defined in ISO
10303-43.</blockquote>
<blockquote class="history">HISTORY&nbsp; New entity in IFC2x.</blockquote>
<p class="spec-head">Informal Propositions:</p>
<ol>
<li>A mapped item shall not be self-defining by participating in the definition of the representation being
mapped.</li>
<li>The dimensionality of the mapping source and the mapping target has to be the same, if the mapping source is a
geometric representation item.</li>
</ol>